The Collaborative International Dictionary of English v.0.48:

Foxy \Fox"y\, a.
   1. Like or pertaining to the fox; foxlike in disposition or
      looks; wily; cunning.
      [1913 Webster]

            Modred's narrow, foxy face.           --Tennyson.
      [1913 Webster]

   2. Having the color of a fox; of a yellowish or reddish brown
      color; -- applied sometimes to paintings when they have
      too much of this color.
      [1913 Webster]

   3. Having the odor of a fox; rank; strong smelling.
      [1913 Webster]

   4. Sour; unpleasant in taste; -- said of wine, beer, etc.,
      not properly fermented; -- also of grapes which have the
      coarse flavor of the fox grape.
      [1913 Webster]

   5. Attractive in a sexually appealing way; --of women.
      [Slang]
      [PJC]

   6. Stylish and sexually attractive; -- of women's clothing;
      as, wearing a foxy new outfit. [Slang]
      [PJC]

WordNet (r) 3.0 (2006):

foxy
    adj 1: marked by skill in deception; "cunning men often pass for
           wise"; "deep political machinations"; "a foxy scheme"; "a
           slick evasive answer"; "sly as a fox"; "tricky Dick"; "a
           wily old attorney" [syn: crafty, cunning, dodgy,
           foxy, guileful, knavish, slick, sly, tricksy,
           tricky, wily]

Moby Thesaurus II by Grady Ward, 1.0:

119 Moby Thesaurus words for "foxy":
   Byzantine, Machiavellian, Machiavellic, Titian, acute, adust,
   alluring, arch, artful, astute, attractive, auburn, bay,
   bay-colored, bayard, besmirched, blackened, brazen, bronze,
   bronze-colored, bronzed, brownish-red, cagey, cagy, calculating,
   canine, canny, castaneous, chestnut, chestnut-brown, clever,
   copper, copper-colored, coppery, crafty, cunning, cupreous, cute,
   darkened, deceitful, deep, deep-laid, designing, devious,
   diplomatic, discolored, dishonest, disingenuous, doggy, feline,
   ferruginous, foxed, foxlike, guileful, henna, ingenious, inky,
   insidious, inventive, knowing, liver-brown, liver-colored,
   livid-brown, lupine, mahogany, murky, pawky, plotting, politic,
   ready, reddish-brown, resourceful, roan, rubiginous, rufous,
   russet, russety, rust, rust-colored, rusty, scheming, seductive,
   serpentine, sexy, sharp, shifty, shrewd, slick, slippery, sly,
   smirched, smoky, smooth, snaky, sneaky, soiled, sophistical,
   stained, stealthy, stigmatic, stigmatiferous, stigmatized,
   strategic, subtile, subtle, sunburned, supple, tactical, tainted,
   tarnished, terra-cotta, trickish, tricksy, tricky, vulpine, wary,
   wily, wise, wolfish